Skip to main content

Full text of "Text Book Of Mechanical Engineering"

See other formats


Appendix VI.

electrically at the firing plug F by the mechanical connection and
separation of small levers within the cylinder. Referring to Fig.
1027, the vertical governor shaft e is driven by speed gear from
the crank shaft, and by the levers at d. When the governor balls
rise on increased speed a sleeve is lifted, which rotates the shaft/
through a small angle and throttles the mixture in. the chamber //
by the lever /, without altering the proportions of gas and air, as
before explained. These proportions can be varied, however, by
the hand lever g, being indicated by the pointer k. The shaft e
further drives the shaft a by 2 : i gear at ^, for the purpose of

raising the inlet levers m-m. The starting is effected very simply
by the admission of compressed air from a bottle previously
charged by the engine power. To do this, a milled nut n is
turned till one of the inlet valves is put out of gear, while the
handle p releases the exhaust cam. This method is equal to-
a barring round of the crank shaft, but in an easier manner, and
the rotation is continued by the ignition of the charge. In this
way, it is said, a 650 H.P. engine can be started with ease by
only one attendant

The Dingier Engine is shewn in section in Fig. 1028, and is
specially interesting from its- method of governing, which reduces